The Tcpdump Group git mirrors - libpcap/blob - inet.c

   1 /* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
   2 /*
   3  * Copyright (c) 1994, 1995, 1996, 1997, 1998
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. All advertising materials mentioning features or use of this software
  15  *    must display the following acknowledgement:
  16  *      This product includes software developed by the Computer Systems
  17  *      Engineering Group at Lawrence Berkeley Laboratory.
  18  * 4. Neither the name of the University nor of the Laboratory may be used
  19  *    to endorse or promote products derived from this software without
  20  *    specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #ifdef HAVE_CONFIG_H
  36 #include "config.h"
  37 #endif
  38
  39 #ifdef _WIN32
  40 #include <pcap-stdinc.h>
  41 #else /* _WIN32 */
  42
  43 #include <sys/param.h>
  44 #ifndef MSDOS
  45 #include <sys/file.h>
  46 #endif
  47 #include <sys/ioctl.h>
  48 #include <sys/socket.h>
  49 #ifdef HAVE_SYS_SOCKIO_H
  50 #include <sys/sockio.h>
  51 #endif
  52
  53 struct mbuf;            /* Squelch compiler warnings on some platforms for */
  54 struct rtentry;         /* declarations in <net/if.h> */
  55 #include <net/if.h>
  56 #include <netinet/in.h>
  57 #endif /* _WIN32 */
  58
  59 #include <errno.h>
  60 #include <memory.h>
  61 #include <stdio.h>
  62 #include <stdlib.h>
  63 #include <string.h>
  64 #if !defined(_WIN32) && !defined(__BORLANDC__)
  65 #include <unistd.h>
  66 #endif /* !_WIN32 && !__BORLANDC__ */
  67
  68 #include "pcap-int.h"
  69
  70 #ifdef HAVE_OS_PROTO_H
  71 #include "os-proto.h"
  72 #endif
  73
  74 #if !defined(_WIN32) && !defined(MSDOS)
  75
  76 /*
  77  * Return the name of a network interface attached to the system, or NULL
  78  * if none can be found.  The interface must be configured up; the
  79  * lowest unit number is preferred; loopback is ignored.
  80  */
  81 char *
  82 pcap_lookupdev(errbuf)
  83         register char *errbuf;
  84 {
  85         pcap_if_t *alldevs;
  86 /* for old BSD systems, including bsdi3 */
  87 #ifndef IF_NAMESIZE
  88 #define IF_NAMESIZE IFNAMSIZ
  89 #endif
  90         static char device[IF_NAMESIZE + 1];
  91         char *ret;
  92
  93         if (pcap_findalldevs(&alldevs, errbuf) == -1)
  94                 return (NULL);
  95
  96         if (alldevs == NULL || (alldevs->flags & PCAP_IF_LOOPBACK)) {
  97                 /*
  98                  * There are no devices on the list, or the first device
  99                  * on the list is a loopback device, which means there
 100                  * are no non-loopback devices on the list.  This means
 101                  * we can't return any device.
 102                  *
 103                  * XXX - why not return a loopback device?  If we can't
 104                  * capture on it, it won't be on the list, and if it's
 105                  * on the list, there aren't any non-loopback devices,
 106                  * so why not just supply it as the default device?
 107                  */
 108                 (void)strlcpy(errbuf, "no suitable device found",
 109                     PCAP_ERRBUF_SIZE);
 110                 ret = NULL;
 111         } else {
 112                 /*
 113                  * Return the name of the first device on the list.
 114                  */
 115                 (void)strlcpy(device, alldevs->name, sizeof(device));
 116                 ret = device;
 117         }
 118
 119         pcap_freealldevs(alldevs);
 120         return (ret);
 121 }
 122
 123 int
 124 pcap_lookupnet(device, netp, maskp, errbuf)
 125         register const char *device;
 126         register bpf_u_int32 *netp, *maskp;
 127         register char *errbuf;
 128 {
 129         register int fd;
 130         register struct sockaddr_in *sin4;
 131         struct ifreq ifr;
 132
 133         /*
 134          * The pseudo-device "any" listens on all interfaces and therefore
 135          * has the network address and -mask "0.0.0.0" therefore catching
 136          * all traffic. Using NULL for the interface is the same as "any".
 137          */
 138         if (!device || strcmp(device, "any") == 0
 139 #ifdef HAVE_DAG_API
 140             || strstr(device, "dag") != NULL
 141 #endif
 142 #ifdef HAVE_SEPTEL_API
 143             || strstr(device, "septel") != NULL
 144 #endif
 145 #ifdef PCAP_SUPPORT_BT
 146             || strstr(device, "bluetooth") != NULL
 147 #endif
 148 #ifdef PCAP_SUPPORT_USB
 149             || strstr(device, "usbmon") != NULL
 150 #endif
 151 #ifdef HAVE_SNF_API
 152             || strstr(device, "snf") != NULL
 153 #endif
 154 #ifdef PCAP_SUPPORT_NETMAP
 155             || strncmp(device, "netmap:", 7) == 0
 156             || strncmp(device, "vale", 4) == 0
 157 #endif
 158             ) {
 159                 *netp = *maskp = 0;
 160                 return 0;
 161         }
 162
 163         fd = socket(AF_INET, SOCK_DGRAM, 0);
 164         if (fd < 0) {
 165                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "socket: %s",
 166                     pcap_strerror(errno));
 167                 return (-1);
 168         }
 169         memset(&ifr, 0, sizeof(ifr));
 170 #ifdef linux
 171         /* XXX Work around Linux kernel bug */
 172         ifr.ifr_addr.sa_family = AF_INET;
 173 #endif
 174         (void)strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
 175         if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0) {
 176                 if (errno == EADDRNOTAVAIL) {
 177                         (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 178                             "%s: no IPv4 address assigned", device);
 179                 } else {
 180                         (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 181                             "SIOCGIFADDR: %s: %s",
 182                             device, pcap_strerror(errno));
 183                 }
 184                 (void)close(fd);
 185                 return (-1);
 186         }
 187         sin4 = (struct sockaddr_in *)&ifr.ifr_addr;
 188         *netp = sin4->sin_addr.s_addr;
 189         memset(&ifr, 0, sizeof(ifr));
 190 #ifdef linux
 191         /* XXX Work around Linux kernel bug */
 192         ifr.ifr_addr.sa_family = AF_INET;
 193 #endif
 194         (void)strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
 195         if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifr) < 0) {
 196                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 197                     "SIOCGIFNETMASK: %s: %s", device, pcap_strerror(errno));
 198                 (void)close(fd);
 199                 return (-1);
 200         }
 201         (void)close(fd);
 202         *maskp = sin4->sin_addr.s_addr;
 203         if (*maskp == 0) {
 204                 if (IN_CLASSA(*netp))
 205                         *maskp = IN_CLASSA_NET;
 206                 else if (IN_CLASSB(*netp))
 207                         *maskp = IN_CLASSB_NET;
 208                 else if (IN_CLASSC(*netp))
 209                         *maskp = IN_CLASSC_NET;
 210                 else {
 211                         (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 212                             "inet class for 0x%x unknown", *netp);
 213                         return (-1);
 214                 }
 215         }
 216         *netp &= *maskp;
 217         return (0);
 218 }
 219
 220 #elif defined(_WIN32)
 221
 222 /*
 223  * Return the name of a network interface attached to the system, or NULL
 224  * if none can be found.  The interface must be configured up; the
 225  * lowest unit number is preferred; loopback is ignored.
 226  *
 227  * In the best of all possible worlds, this would be the same as on
 228  * UN*X, but there may be software that expects this to return a
 229  * full list of devices after the first device.
 230  */
 231 #define ADAPTERSNAME_LEN        8192
 232 char *
 233 pcap_lookupdev(errbuf)
 234         register char *errbuf;
 235 {
 236         DWORD dwVersion;
 237         DWORD dwWindowsMajorVersion;
 238         char our_errbuf[PCAP_ERRBUF_SIZE+1];
 239
 240 #pragma warning (push)
 241 #pragma warning (disable: 4996) /* disable MSVC's GetVersion() deprecated warning here */
 242         dwVersion = GetVersion();       /* get the OS version */
 243 #pragma warning (pop)
 244         dwWindowsMajorVersion = (DWORD)(LOBYTE(LOWORD(dwVersion)));
 245
 246         if (dwVersion >= 0x80000000 && dwWindowsMajorVersion >= 4) {
 247                 /*
 248                  * Windows 95, 98, ME.
 249                  */
 250                 ULONG NameLength = ADAPTERSNAME_LEN;
 251                 static char AdaptersName[ADAPTERSNAME_LEN];
 252
 253                 if (PacketGetAdapterNames(AdaptersName,&NameLength) )
 254                         return (AdaptersName);
 255                 else
 256                         return NULL;
 257         } else {
 258                 /*
 259                  * Windows NT (NT 4.0 and later).
 260                  * Convert the names to Unicode for backward compatibility.
 261                  */
 262                 ULONG NameLength = ADAPTERSNAME_LEN;
 263                 static WCHAR AdaptersName[ADAPTERSNAME_LEN];
 264                 size_t BufferSpaceLeft;
 265                 char *tAstr;
 266                 WCHAR *Unameptr;
 267                 char *Adescptr;
 268                 size_t namelen, i;
 269                 WCHAR *TAdaptersName = (WCHAR*)malloc(ADAPTERSNAME_LEN * sizeof(WCHAR));
 270                 int NAdapts = 0;
 271
 272                 if(TAdaptersName == NULL)
 273                 {
 274                         (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "memory allocation failure");
 275                         return NULL;
 276                 }
 277
 278                 if ( !PacketGetAdapterNames((PTSTR)TAdaptersName,&NameLength) )
 279                 {
 280                         pcap_win32_err_to_str(GetLastError(), our_errbuf);
 281                         (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 282                                 "PacketGetAdapterNames: %s", our_errbuf);
 283                         free(TAdaptersName);
 284                         return NULL;
 285                 }
 286
 287
 288                 BufferSpaceLeft = ADAPTERSNAME_LEN * sizeof(WCHAR);
 289                 tAstr = (char*)TAdaptersName;
 290                 Unameptr = AdaptersName;
 291
 292                 /*
 293                  * Convert the device names to Unicode into AdapterName.
 294                  */
 295                 do {
 296                         /*
 297                          * Length of the name, including the terminating
 298                          * NUL.
 299                          */
 300                         namelen = strlen(tAstr) + 1;
 301
 302                         /*
 303                          * Do we have room for the name in the Unicode
 304                          * buffer?
 305                          */
 306                         if (BufferSpaceLeft < namelen * sizeof(WCHAR)) {
 307                                 /*
 308                                  * No.
 309                                  */
 310                                 goto quit;
 311                         }
 312                         BufferSpaceLeft -= namelen * sizeof(WCHAR);
 313
 314                         /*
 315                          * Copy the name, converting ASCII to Unicode.
 316                          * namelen includes the NUL, so we copy it as
 317                          * well.
 318                          */
 319                         for (i = 0; i < namelen; i++)
 320                                 *Unameptr++ = *tAstr++;
 321
 322                         /*
 323                          * Count this adapter.
 324                          */
 325                         NAdapts++;
 326                 } while (namelen != 1);
 327
 328                 /*
 329                  * Copy the descriptions, but don't convert them from
 330                  * ASCII to Unicode.
 331                  */
 332                 Adescptr = (char *)Unameptr;
 333                 while(NAdapts--)
 334                 {
 335                         size_t desclen;
 336
 337                         desclen = strlen(tAstr) + 1;
 338
 339                         /*
 340                          * Do we have room for the name in the Unicode
 341                          * buffer?
 342                          */
 343                         if (BufferSpaceLeft < desclen) {
 344                                 /*
 345                                  * No.
 346                                  */
 347                                 goto quit;
 348                         }
 349
 350                         /*
 351                          * Just copy the ASCII string.
 352                          * namelen includes the NUL, so we copy it as
 353                          * well.
 354                          */
 355                         memcpy(Adescptr, tAstr, desclen);
 356                         Adescptr += desclen;
 357                         tAstr += desclen;
 358                         BufferSpaceLeft -= desclen;
 359                 }
 360
 361         quit:
 362                 free(TAdaptersName);
 363                 return (char *)(AdaptersName);
 364         }
 365 }
 366
 367
 368 int
 369 pcap_lookupnet(device, netp, maskp, errbuf)
 370         register const char *device;
 371         register bpf_u_int32 *netp, *maskp;
 372         register char *errbuf;
 373 {
 374         /*
 375          * We need only the first IPv4 address, so we must scan the array returned by PacketGetNetInfo()
 376          * in order to skip non IPv4 (i.e. IPv6 addresses)
 377          */
 378         npf_if_addr if_addrs[MAX_NETWORK_ADDRESSES];
 379         LONG if_addr_size = MAX_NETWORK_ADDRESSES;
 380         struct sockaddr_in *t_addr;
 381         unsigned int i;
 382
 383         if (!PacketGetNetInfoEx((void *)device, if_addrs, &if_addr_size)) {
 384                 *netp = *maskp = 0;
 385                 return (0);
 386         }
 387
 388         for(i = 0; i < if_addr_size; i++)
 389         {
 390                 if(if_addrs[i].IPAddress.ss_family == AF_INET)
 391                 {
 392                         t_addr = (struct sockaddr_in *) &(if_addrs[i].IPAddress);
 393                         *netp = t_addr->sin_addr.S_un.S_addr;
 394                         t_addr = (struct sockaddr_in *) &(if_addrs[i].SubnetMask);
 395                         *maskp = t_addr->sin_addr.S_un.S_addr;
 396
 397                         *netp &= *maskp;
 398                         return (0);
 399                 }
 400
 401         }
 402
 403         *netp = *maskp = 0;
 404         return (0);
 405 }
 406
 407 #endif /* !_WIN32 && !MSDOS */